UPDATE t1 SET
a=(SELECT a FROM t2 WHERE id=t1.id),
b=(SELECT b FROM t2 WHERE id=t1.id),
c=(SELECT c FROM t2 WHERE id=t1.id),
d=(SELECT d FROM t2 WHERE id=t1.id);
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SQLite批量更新效率问题
最近一个新项目接触到SQLite数据库,发现一段语句执行时间很长,貌似没有联表更新 这样效率很低,求大神指点一二 UPDATE t1 SET a=(SELECT a FROM t2 WHERE id=t1.id), b=(SELECT b FROM t2 WHERE id=t1.id), c=(SELECT c FROM t2 WHERE id=t1.id), d=(SELECT d FROM t2 WHERE id=t1.id);